Advancing Circular Bioeconomy through Innovation

World Environment Day is a global reminder of the urgent need to accelerate sustainable solutions that reduce waste, lower emissions, and make better use of natural resources. In line with these objectives, the CHEERS project is demonstrating how industrial side streams from the brewing sector can be transformed into valuable bio-based products, contributing to a more circular and resource-efficient economy.

Through a combination of microbial, insect-based, and bioprocessing technologies, CHEERS is developing innovative pathways that convert brewery by-products, fermentation gases, wastewater, and biogas into high-value ingredients and products for animal nutrition, cosmetics, and industrial applications.

Turning Waste into Value

One of the key principles promoted by World Environment Day is the transition from a linear “take-make-dispose” model to a circular economy where resources remain in productive use for as long as possible. CHEERS embodies this principle by applying cascading valorisation strategies to brewery side streams that would otherwise have limited economic value.

The project’s technology platforms demonstrate how biological systems can recover carbon, nutrients, and organic matter, converting them into new products while reducing environmental impacts associated with waste management and resource extraction.

Microbial Conversion of Methane into Sustainable Protein

A significant achievement within CHEERS is the development of a microbial platform that converts methane-rich biogas into Single Cell Protein (SCP), a sustainable alternative protein source for pet food applications.

Using a forced-circulation loop bioreactor, methane is biologically transformed into high-protein microbial biomass, achieving methane bioconversion rates of up to 83% and protein contents of 56% in the resulting biomass.

This approach addresses two environmental challenges simultaneously: reducing methane emissions—a potent greenhouse gas—and producing alternative protein ingredients that can help decrease reliance on conventional feed resources. Consumer validation activities involving dog owners have also demonstrated the potential acceptance of these novel protein products.

Insect-Based Bioconversion of Brewery By-Products

CHEERS is also advancing insect farming technologies that utilise brewery bagasse and yeast side streams as feed substrates for Tenebrio larvae production. The insect platform successfully converts these residual materials into high-value insect protein ingredients while recovering nutrients that would otherwise remain underutilised.

Experimental trials demonstrated that different feeding strategies can tailor the nutritional composition of the insect biomass, increasing either protein, dietary fibre, lipid, or carbohydrate content depending on the formulation.

The optimised system is estimated to valorise between 78.85 and 118.28 tonnes of brewery bagasse annually while producing up to 15.32 tonnes of insect biomass.

By creating alternative protein sources from industrial side streams, the technology contributes directly to more sustainable food and feed systems, supporting the goals of resource efficiency and waste reduction highlighted by World Environment Day.

Capturing and Upgrading CO₂ into Valuable Products

Carbon dioxide generated during beer fermentation is often viewed as a waste stream. Within CHEERS, however, CO₂ becomes a valuable resource.

The project has developed a microbial CO₂-to-caproic acid value chain that converts fermentation-derived CO₂, brewery wastewater, and ethanol-rich side streams into caproic acid-rich products for animal nutrition applications.

The process achieves CO₂ conversion efficiencies between 70% and 80%, while gas recycling strategies further improve process performance and resource utilisation.

This technology demonstrates how industrial carbon emissions can be transformed into marketable products, supporting climate mitigation objectives while creating new economic opportunities for bio-based industries.

Sustainable Production of Cosmetic Ingredients

Another innovative pathway within CHEERS focuses on the biological production of ectoine, a high-value ingredient widely used in cosmetic formulations.

Using methane as a feedstock, halotolerant methanotrophic microorganisms convert CH₄ into ectoine-rich biomass within a Taylor Flow bioreactor.

The system has achieved methane bioconversion rates of up to 92% and ectoine yields reaching 50 g-Ect/gVSS.

The pilot-scale technology has been installed at the Lleida wastewater treatment plant, where operational conditions are being optimised to maximise sustainability and productivity.

This approach illustrates how greenhouse gases can serve as raw materials for the production of high-value bio-based compounds, reinforcing the circular economy principles celebrated on World Environment Day.

Circular Solutions for Water Treatment

CHEERS also demonstrates circularity through the production of sodium hypochlorite-based disinfectants derived from brine generated during the ectoine production process.

Through electrochlorination, residual streams are converted into disinfectant solutions suitable for water treatment applications, achieving production capacities of 42 litres per hour.

By integrating multiple valorisation routes within a single ecosystem, the project maximises resource efficiency while minimising waste generation across the entire value chain.

A European Collaboration for Environmental Impact

The CHEERS project brings together 12 partners from five European countries, combining expertise in biotechnology, process engineering, sustainability, industrial operations, and citizen engagement.

Through this collaborative approach, the project is creating scalable solutions that support the European Green Deal, circular bioeconomy strategies, and climate neutrality objectives.

As World Environment Day highlights the importance of restoring ecosystems, reducing pollution, and promoting sustainable production systems, CHEERS provides a practical example of how innovation can contribute to these goals.

By transforming brewery side streams, methane, carbon dioxide, and wastewater into valuable proteins, cosmetic ingredients, animal nutrition products, and disinfectants, the project demonstrates that waste can become a resource and emissions can become opportunities.

Through these innovations, CHEERS is helping build a more circular, resilient, and sustainable future for Europe’s bioeconomy.